This invention relates to fluid eductor devices for injecting a secondary fluid into a flowing primary fluid. More particularly, this invention relates to fluid eductor devices for injecting a gas such as air, oxygen, ozone or other reactant fluids into a liquid such as water, sewage or other reactant fluids flowing along a conduit.
Devices are known for injecting a secondary fluid, such as a gas, into a primary fluid, such as a liquid, flowing within a conduit. While such devices have found wide use in many applications, perhaps the most common application is the problem of oxygen depleted water. Discharge water from many different types of plant installations, such as chemical, petroleum, paper/pulp and pharmaceutical plants, as well as food process facilities and sewage treatment facilities, is frequently deficient in the concentration of oxygen dissolved therein. This oxygen deficiency imposes a severe oxygen demand on receiving waters or in subsequent treatment facilities.
In order to remedy this deficiency, the discharge waters are typically oxygenated in the feed streams by the injection of oxygen or air in order to improve the quality of the discharge water for subsequent use. Examples of devices used for this purpose in the past are diffused aerator units, swing diffusers, surface aerator installations, turbine aerators and spargers. While generally effective in oxygenating the discharge waters, such known units are expensive to install, operate and maintain, and also impose a power demand which must be met by the consumption of increased power by the associated facility. This increase in power consumption raises the overall cost of the operation and is accordingly undesirable. To date, efforts to devise fluid injection systems which are economical and uncomplicated have not met with wide success.